A report this week claims that nearly 90 percent of Microsoft-sponsored search results for online pharmacies found by the Bing search engine lead to fraudulent sites.

Soaring health costs are driving more consumers to buy the drugs they need online. At the same time, finding legitimate online pharmacies that sell legitimate and safe drugs has become a much more risky venture.

The statistics from the new report, which examines only sponsored search results on Microsoft's (NASDAQ: MSFT) Bing search engine, paint a bleak picture -- potentially signaling that consumers may be placing themselves in danger by following Bing's links to illegitimate sites.

"Of the prescription drug and online pharmacy advertisements sponsored by Microsoft that we reviewed, 89.7 percent led to 'rogue' Internet pharmacies that do not require a prescription for prescription drugs, or are otherwise acting unlawfully or fraudulently," the report said. That included sites, in at least one test instance, that were caught selling counterfeit pharmaceuticals.

The report is a collaboration between online pharmacy verification firm LegitScript and Internet compliance tracking firm KnujOn. It is the first of a planned series on search issues, KnujOn CEO Garth Bruen told InternetNews.com.

The authors, including Bruen, said their companies funded the research without the backing of any third parties.

Part of the reason why Microsoft got picked to be first is because its new Bing search engine, which it markets as a "decision engine," aims to focus on five specific and lucrative areas of expertise, including health.

Microsoft launched Bing in late May to great fanfare. Since then, it has seen slight gains in Microsoft's share of online U.S. searches.

However, the new report focused only on Microsoft-sponsored Bing search results for pharmaceuticals.

"There are thousands and thousands of possible prescription drug searches," Tom Horton, president of LegitScript, told InternetNews.com. "We looked at ten different prescription drug searches involving a total of 69 sponsored search results."

Neither were the bogus ads just a flash in the pan. "One thing not directly mentioned in the report but that's important is none of the illicit search results were just up for a day or two, and then taken down," Horton said in a follow-up e-mail.

Besides sites that sell drugs without a prescription, other problems cited in the report are legitimate-seeming sites that, at the last minute, redirect users to sites in countries like Russia and China -- in some cases linked to organized crime -- as well as sites that sell counterfeit drugs.

Drug searches in the test included queries seeking erectile dysfunction drugs Cialis, Viagra, and Levitra, as well as anti-depressants like Wellbutrin and sleeping pills like Ambien and Soma. The authors ordered some of the drugs and in at least one case found that they were sent counterfeit drugs from a company in India, the report said.

"We take these claims very seriously and are currently investigating this issue," a Microsoft spokesperson told InternetNews.com in an e-mail. "Microsoft's guidelines clearly require online pharmacies who advertise on Bing to adhere to U.S. laws."

Microsoft, overall, has a fairly good record of dealing with questionable material found by its search properties, including the newly launched Bing. When confronted in June with problems of Bing users getting unexpectedly easy access to porn, Microsoft moved quickly to fix the issue.

This week's report also admits that Microsoft "has a policy in place to limit ads for pharmacies, or prescription drugs, to [verified] ... pharmacies."

One of the report's complaints regarding Bing searches, however, is that Microsoft does not appear to actively police such advertisers -- and that the company has a financial interest in users who click through to the false advertisers, generating a small bit of revenue as a result.

"Just because you find something on the Internet doesn't mean it's safe or legitimate," Bruen added. "Anybody can set up a Web site and sell junk over the Internet."

The report can be found on LegitScript's site, and is available here in PDF format.